Differential Diagnosis for Progressive Leg Swelling in a 65-year-old Man with Type 2 Diabetes Mellitus and Hypertension
- Single most likely diagnosis:
- Chronic Kidney Disease (CKD) with Nephrotic Syndrome: The patient's long history of uncontrolled hypertension, type 2 diabetes mellitus, and positive urine microalbumin concentration for 3 years suggest chronic kidney damage. The recent increase in leg swelling, despite increasing the dosage of hydrochlorothiazide, and the laboratory findings of elevated serum creatinine (2.5 mg/dL), low serum albumin (2.9 g/dL), and significant proteinuria (2+ protein on urinalysis) support this diagnosis.
- Other Likely diagnoses:
- Diabetic Nephropathy: Given the patient's history of type 2 diabetes mellitus and the presence of microalbuminuria, diabetic nephropathy is a likely contributor to his kidney dysfunction.
- Hypertensive Nephrosclerosis: Uncontrolled hypertension can lead to kidney damage, and the patient's difficulty in controlling blood pressure suggests that hypertensive nephrosclerosis could be a contributing factor to his kidney disease.
- Heart Failure: Although not directly indicated by the laboratory findings, the patient's history of hypertension and the presence of leg swelling could suggest heart failure as a possible cause of his symptoms, especially if the kidney disease is secondary to heart failure.
- Do Not Miss diagnoses:
- Renal Artery Stenosis: This condition, often associated with uncontrolled hypertension, could lead to kidney dysfunction and should be considered, especially given the patient's difficulty in controlling blood pressure.
- Obstructive Uropathy: Although less likely, obstructive uropathy could cause kidney dysfunction and should be ruled out, especially if there are symptoms or signs suggestive of urinary obstruction.
- Rare diagnoses:
- Amyloidosis: A rare condition that can cause nephrotic syndrome and kidney dysfunction. It would be considered if other more common causes are ruled out and if there are other systemic symptoms suggestive of amyloidosis.
- Membranous Nephropathy or Other Glomerulopathies: These are less common causes of nephrotic syndrome and would be considered if biopsy is necessary to determine the cause of kidney disease and other diagnoses are ruled out.